Mechanical driving mechanism



Oct. 26, 1937. A. 'r. KELLER 2,097,282

' MECHANICAL DRIVING MECHANISM Filed April 18, 1934 2 Sheets-Sheet 1Oct. 26, 1937. A. T. KELLER 2 2,097,282

MECHANICAL DRIVING MECHANISM Filed April 18, 1954 2 Sheets-Sheet 2 v IZ; n

gnvcntoz @672 ZIllair Patented Oct. 26, 1937 UNITED STATS MECHANICALDRIVING MECHANISM Albert T. Keller, Bethlehem, Pa., assignor toBethlehem Steel Company, a corporation of Pennsylvania Application April18, 1934, Serial No. 721,078

1'7 Claims.

This invention relates to the drive of a rolling mill by which the millis reversed while the prime mover driving it maintains its revolution ina given direction. It is particularly useful in 5 connection with sheetor tin plate mills where frequent reversals are desirable, which foreconomy must be performed in the shortest possible interval of time.Hitherto in rolling mills reversal has been accomplished by reversingthe electric motor driving the mill, by reverse gearing or by othermeans which in general are not suitable for the very rapid reversalscorresponding to the short passes of sheet and tin plate mills. For thisreason such mills are run con- ]5 tinuously in one direction, the workafter a pass being carried over the top of the rolls and given the nextpass in the same direction. In the present invention a friction drive isemployed which is preferably arranged to drive both rollssimultaneously. The friction drive is designed with power to transmitthe heavy torques required for rolling and at the same time is arrangedso that a small movement of certain of the parts suffices to bring abouta reversal, the power for causing this movement preferably beingfurnished by hydraulic cylinders. At the time of reversal a certainamount of slip must take place between the friction elements in order toaccelerate the rolls. These elements must be of such a character thatthey can slip with a minimum of damage under heavy pressure, can bereadily redressed to correct for unequal wear and are simple andrelatively cheap to replace.

Referring to the drawings:

Fig. 1 is a side elevation showing one embodiment of the reversingmechanism connected to drive the rolls of a sheet mill; Fig. 2 is an endelevation partly in section of the reversing mechanism shown in Fig. 1;Fig. 3 is a diagrammatic drawing of the piping arrangements forcontrolling the mechanism.

In the drawings H and I2 are rolls of a sheet mill positioned in housingl3 and driven by spindles l4 and I5 through universal couplings i5 andH. These spindles in turn receive their drive from shafts l8 and I9 ofreversing mechanism 20. This mechanism comprises the four drums 2|, 22,23, and 24 held in bearings in housing members 25. The shaft of drum 2|is provided with Wobbler 26 which receives a drive continuously in thedirection of the arrow from an outside source of power and is mounted inrelatively fixed journal bearing blocks, one of which is shown at 21,supported by the housing but adapted for adjustment horizontally in a.

direction transverse to the drum axis. 22 indicates a driven idler drumlikewise held in relatively fixed journal bearing blocks one of which isshown at 28 and which are also adapted for adjustment in the housing, ispressed in frictional driving contact with drum 2|, a heavy surfacepressure between the two drums being maintained by screws 29 threaded inthe housing and pressing against the outer surfaces of bearing blocks 21and 28. Drum 23 is held in bearingblocks one of which is shown at 39.These can be moved horizontally in the housing transversely of the drumaxis by means of stems 3| integrally attached to the bearing blocks andactuated longitudinally by pistons 32 and 33 in fluid pressure cylinders34 and 35, which latter are rigidly attached to the housing. Drum 23 maythus be brought either into surface driving contact with drum 22 asshown in the drawings or, by moving the bearing block to the left intocontact with drum 2|, the direction of revolution in the former casebeing clockwise on Fig. 2 and in the latter counterclockwise. Byactuating the fluid pressure cylinders so as to position the drum halfway between the right and left hand positions the driving connectionwill be entirely broken. Stems .3l serve not only to transmit the thrustof the pistons to the bearing blocks but to support the weight of theblocks and drum as well, seats as shown at 36 being provided for thestems to slide on.. The upward thrust of the drum when in the drivingpositions is taken by the surface 31, and a similar surface on the otherhousing member.

Lower drum 24 is held in bearing blocks one of which is shown at 39.These can be moved horizontally in the housing transversely of the drumaxis by means of stems 40 one of which presses against each side of eachof the bearing blocks. The stems are integral with pistons M and 42 offluid pressure cylinders 43 and 44 which are rigidly attached to thehousing. This drum like drum 23 may thus be brought into driving contactwith drum 2| or the driven idler drum 22 or may be brought to a neutralposition where the driving connection is broken. Bearing blocks 39 aresupported by a flat surface shown at 45 and a similar surface on theother housing member, these surfaces serving also to take the downwardthrust when the drum is in the driving positions.

Housing members 25 are made with body portions 45 and caps 41 fastenedby bolts 48. By releasing these bolts and removing the caps the drumsand their bearings may be lifted out for regrinding or replacement.

In Fig. 3 is shown diagrammatically a suitable arrangement of valves andpipe for controlling the fluid pressure cylinders. The two cylinders 34by which drum 23 is forced to the right in Fig. 2 are connected to pipe5!, while the two cylinders 44, by which drum 24 is forced to the leftare connected to pipe 52, cylinders 35 by which drum 23 is forced to theleft are connected to pipe 53 and cylinders 43 by which drum 24 isforced to the right are connected to pipe 54. In this manner ofarrangement the pressure of the cylinders upon each side of the housingis balanced or equalized. Pipes 5! and 52 unite in the common pipe whilepipes 53 and 54 unite in the common pipe 56. Valve 51 showndiagrammatically is arranged to connect pipe 55 with pipe 58, to asource of high pressure fluid, and pipe 56 with drain pipe 59 oralternatively to connect pipe 55 with pipe 59 and pipe 56 with pipe 58,handle 60 causing the shift from one condition to the other. In theintermediate position of the handle, flow is cut off from pipes 55 and56. In one extreme position of the handle the upper drum will be forcedto the left and the lower drum to the right, in the other extremeposition the opposite movement will take place, while in theintermediate position the drums can be held in any desired relation.Valves 6! are placed in the pipes leading to each cylinder to correctlyapportion the flow to and from each of them and to permit individualoperation of any cylinder or group of cylinders.

A typical example of the operation of this mill in producing tin plateis as follows. Two lengths of tin bar delivered from the heating furnaceare passed in succession through the rolls with the drive set in theforward direction. The drums of the reversing gear are then shifted tothe neutral position, held there for a moment while the friction in theroll and drum necks brings the rolls to a stop. The drums are thenshifted to the further extremity causing the rolls to drive in thereverse direction, the partially rolled bars are fed back through therolls in reverse order. This back and forth rolling is continued, thebars being matched when properly reduced in thickness, and finally thepair is removed from the rolls, doubled, reheated and the rollingprocess repeated.

In this process the work of the catcher, whether a man or machine isemployed for the purpose is very slight and can be performed rapidly.Moreover the reversing cycle may be made very short. Assuming a speed of35 R. P. M. on the rolls of an ordinary sheet or tin mill and acoefiicient of friction on the bearings of 10% the drive with spindlesand rolls will stop in about 1 seconds by simply breaking the contactbetween the friction drums. To bring the spindles and rolls from rest upto 35 R. P. M. with a pressure of 80,000 pounds between the frictiondrums will require about the same period. If the actual time of the passis of a second the total time for a pass and reversal will be about 3seconds, or 18 cycles per minute. With a skilled operator who knows howmuch drifting takes place under varying conditions of draft, the numberof cycles can be increased by disengaging the friction drums before theend of a pass and allowing the bar or sheet to slow the rolls nearly torest'as they completethe pass. The friction drums may also be throwninto a reverse driving position before the rolls have come completely torest.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. In a mechanical drive, a first drum, means to drive said first drumfrom an external source of power, a second drum, means to hold saidfirst and said second drums in rolling contact,

third and fourth drums, selective means to force said third drum intorolling contact with said first drum and said fourth drums into rollingcontact with said second drum or said third drum into rolling contactwith said second drum and said fourth drum into rolling contact withsaid third drum, and driven means operatively connected with said thirdand said fourth drums.

2. In a rolling mill drive, a housing, a first drum, bearings for saidfirst drum slidably held in said housing, a second drum, bearings forsaid second drum slidably held in said housing, adjustable meanspressing against said bearings to force said first and second drums intorolling contact, a third drum, bearings for said third drum slidablyheld in said housing, controllable means pressing against said lastmentioned bearings to force said third drum into rolling contact withsaid first drum and with said second drum respectively, a fourth drum,bearings for said fourth drum slidably held in said housing, andcontrollable means pressing against said last mentioned bearings toforce said fourth drum into rolling contact with said first drum andwith said second drum respectively.

3. In a rolling mill drive, a housing, a first drum, bearings for saidfirst drum slidably held in said housing, a second drum, bearings forsaid second drum slidably held in said housing, adjustable meanspressing against said bearings to force said first and second drums intorolling contact, a third drum, bearings for said third drum slidablyheld in said housing, controllable means pressing against said lastmentioned bearings to force said third drum into rolling contact withsaid first drum and with said second drum respectively, a fourth drum,bearings for said fourth drum slidably held in said housing,controllable means pressing against said last mentioned hearings toforce said fourth drum into rolling contact with said first drum andwith said second drum respectively, and means for simultaneouslyactuating said first mentioned and said second mentioned controllablemeans.

4. A reversing drive, comprising a driving drum and a driven idler drum.adapted to be held in frictional contact therewith, relatively fixedjournal bearings for the driving drum and the driven idler drum, a. pairof driven drums mounted in movable journalbearings, fluid pressure meansfor alternately moving the pair of driven drums simultaneously intofrictional engagement under pressure with the driving drum and thedriven idler drum, and means for holding the pair of driven drums in aneutral position out of engagement with the driving drum and the drivenidler drum.

v 5. A reversing drive, comprising a driving drum and a driven idlerdrum. adapted to be held at all times in frictional contact with eachother, relatively fixed journal bearings for the driving drum and thedriven idler drum, a pair of driven drums mounted in movable journalbearings, and fluid pressure means for alternately holding one of thepair of driven drumsinfric tional engagement with the driving drum andthe other in frictional engagement with the driven idler drum. 1

6. A reversing drive, comprising a driving drum and a driven idler drumfrictionally engaging each other mounted in relatively fixed journalbearings, a pair of driven drums mounted in movable journal bearingsengaging the driving drum and the driven idler drum, and fluid pressuremeans connectedto themovable journal bearings adapted to alternatelyforce each of the pair of driven drums simultaneously in oppositedirections into engagement with the driving drum or the driven idlerdrum.

7. A reversing drive, comprising a housing, a driving drum and a drivenidler drum frictionally engaging each other and mounted in relativelyfixed journal bearings in the housing, a pair of driven drums mounted inmovable journal bearings in the housing each adapted to frictionallyengage the driving drum or the driven idler drum on opposite surfaces,slideways formed in the housing for the movable journal bearings, fluidpressure means for simultaneously forcing one of the said pair of drivendrums into frictional engagement with the driving drum and the otherinto frictional engagement with the driven idler drum, and fluidpressure means for simultaneously reversing the positions of the pair ofdriven drums to force the one engaging the driving drum into frictionalengagement with the driven idler drum and the other into frictionalengagement with the driving drum.

8. A reversing drive, comprising a housing, a driving drum and a drivenidler drum frictionally engaging each other and mounted in relativelyfixed bearing blocks in the housing, means for adjusting the relativelyfixed bearing blocks, a pair of driven drums mounted in movable bearingblocks each adapted to frictionally engage the driving drum or thedriven idler drum on opposite surfaces, slideways formed in the housingfor the movable journal bearing blocks, fluid pressure means forsimultaneously reciprocating the movable journal bearing blocks to forceone of the pair of driven drums into frictional engagement with thedriven idler drum, and means for controlling the fluid pressure toreverse the positions of the pair of driven drums in their relation tothe driving drums and the driven idler drum.

9. A reversing drive, comprising a housing, a driving drum and a drivenidler drum mounted in relatively fixed journal bearings in the housingand frictionally engaging each other, means for adjusting the relativelyfixed journal bearings, a pair of driven drums mounted in movablejournal bearings each adapted to alternately engage the driving drum orthe driven idler drum on opposite surfaces, slideways formed in thehousing for the movable journal bearings, a piston on opposite sides ofeach movable journal hearing, a fluid pressure cylinder for each piston,and means for controlling the fluid supply to the cylinders forsimultaneously reciprocating the movable journal bearings for one ofsaid pair of driven drums in the reverse direction to that of the otherone of said pair of driven drums.

10. A reversing drive, comprising a driving drum and a driven idler drumadapted to be held in frictional contact by relatively fixed journalbearings, a pair of driven drums mounted in movable journal bearingsadapted to alternately frictionally engage the driving drum. and

theidriven idler. drum, and means for simultaneously sliding the movablejournal bearings for each of the pairzof driven drumsin oppositedirections;

11.,A reversing drive, comprising a housing, a driving drum and a drivenidler drum horizontally disposed and adapted to be held in frictionalcontact by relatively fixed-journal bearings, an upperandlower drivendrum mounted in movable journal bearings adapted to frictionally engageopposite surfaces of thedriving drum and the driven idler drum,slideways and seats formed in the upper portion of the housing, stemsintegrally connected to the movable journal bearings and slidablymounted in the seats for supporting the movable journal bearings for thetop driven drum, a piston formed on the outer end of each stem, a fluidpressure cylinder for each piston secured to the side of the housing,slideways formed in the lower portion of the housing for supporting themovable journal bearings for the lower driven drum, stems slidable inthe housing for engaging opposite sides of the movable journal bearingsfor the lower driven drum each having a piston formed on their outerend, fluid pressure cylinders for said pistons secured to the housing,and means for controlling the fluid pressure to and from the cylinders.

12. In a mechanical drive, a first drum, means to drive said first drumfrom an external source of power, a second drum, relatively fixedjournal bearings for holding said first and said second drums in rollingcontact, a third drum, means to force said third drum alternately intorolling contact with said first and with said second drums respectively,a fourth drum, and means operated simultaneously with the operatingmeans for the third drum to force said fourth drum alternately intorolling contact with the second and said first drums respectively.

13. A reversing drive, comprising a driving drum and a driven idler drumeach mounted in relatively fixed journal bearings and frictionallyengaging each other, a pair of driven drums mounted in movable journalbearings adapted to frictionally engage the driving drum and the drivenidler drum in alternate relation to each other, and means forsimultaneously reciprocating the movable journal bearings for one of thepair of driven drums in opposite directions to that of the other drivendrum.

14. A reversing drive, comprising a driving drum and a driven idler drumheld in frictional contact with said driving drum, relatively fixedbearings for the driving drum and the driven idler drum, a pair ofdriven drums mounted in movable journal bearings each adapted toalternately frictionally engage the opposite surfaces of the drivingdrum and the driven idler drum, and fluid pressure means for holding thepair of driven drums in frictional contact with the driving drum and thedriven idler drum.

15. A reversing drive, comprising a driving drum and a driven idler drumadapted to be held in frictional contact with the driving drum,relatively fixed bearings for the driving drum and the idler drivendrum, means for adjusting the relatively fixed bearings for the drivingdrum and the driven idler drum, a pair of driven drums mounted inmovable journal bearings each adapted to alternately frictionally engagethe driving drum and the driven idler drum, and fluid pressure means forsimultaneously reciprocating the movable journal bearings for each ofthe pair of driven drumsin opposite directions.

16. A reversing drive, comprising a driving drum, an idler drum adaptedto frictionally engage the driving drum, fixed bearings for the drivingdrum and the driven idler drum, and a pair of driven drums each mountedin oppositely movable journal bearings each adapted to simultaneouslyalternately engage and be driven by the driving drum and the drivenidler drum.

1'7. A reversing drive, comprising a driving ALBERT T. KELLER.

